Drill-heating furnace



W 17 H. K. FOX

DRILL HEATING FURNACE Filed March 15. 1926 2 Sheets-Sheet INVENTOR. HAROLD A- X BY A TTORNEYS.

1,628 964 May 17 1927. H. K. F

DRILL HEATING FURNACE Filed March 15. 1926 2 Sheets-Sheet 2 INVENTOR.

fMROLD A. F X

A TTORNEYS.

' Patented May 17, 1927.

A 1,628,964 UNITED STATES PATENT OFFICE.

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This invention relates to furnaces adapted to the heating of rockdrills and the likefor forging, sharpening or tempering of the same. a

The objects of the invention are to provide a furnace of the type mentioned which will be heated by electricity with its heating elements under group control and arranged in a certain way relative to the tools so as 10 to provide a. maximum and even distribution of heat, together with provisions for conserving the heat while promoting rapid handling of the tools, and at the same time protecting the tools from heat where not 1 desired. v The novel arrangement of furnace elements also provides for giving a reading of the heat in the tool zone of the furnace as distinguished from the general furnace 2 chamber temperature, and also 1 provides other advantageous features of construction as will appear in the following description. In the drawings hereto Figure 1 is'a front elevation of my furnace and Figure 2 an :5 end view in cross section as taken along'the line 2-2 of Figure 1. a Generally described my furnace comprises a furnace body with an elongated chamber 1 therein traversed transversely by bar like electric heating elements 2 spaced along the chamber, while the tools 3 are inserted through a slot 4 extending along one side of the body, and when inserted the tools project between the rows of heating elements.

The slot is preferably arran d with an enlarged portion 4 at each en so that the tools must be inserted at one endof the slot, passed along the slot, and removed from the other enlarged end. I

Preferably also tho not necessarily the slot (furnace included if desired) is inclined downwardly toward the removal end of the slot so that when the slot is full of tools and one is removed the others will roll downward, or may easily be pushed down-' ward so as to accommodate another cold tool at the receiving end of the slot. In further detail the furnace body comprises iron frame members 5 enclosing and supporting within it various suitable refractory blocks 6, 7, 8, 9, 10, 11. and 12, arranged to form the chamber 1 and properly surroupaded with concrete or other material as at v The blocks '9 and are supported in' heating elements 2.

' conducting spaced relation as shown to form the slot 4 and at the outer ed e of the slot is an iron angle 5' raised a s ort distance above the bottom of the slot so that a tool 3 when in place will extend at a slight angle from the iron 5' to the inner'corner of the slot and thereby leave an air passage around its shank to prevent undue heating of the shank, while adjacent the inner ed e of iron 5 is a block of especially good eatinsulating material 14 such as silocel to additionally protect the shanks from overheat-, a

The blocks 11 and 12 are tubular and arranged in s aced confronting relation so as to receive t erethrough a series of electrical It is of course optional just which type of heating element is used tho I prefer a rod or bar type now on the market and which will stand a high heat without sag-v ging into the chamber.

These bars 2 are supported in the ends of plugs 15 surrounded by alundum sleeves 15 and receive their energizing current through a series of heavy contact springs 16 mounted on the front and rear furnace walls and suitably connected by bus bars 17.

It is contemplated that some or all of the heating elements be wired in groups connected by smaller bus bars 17 panel 19. The controlling switches and wirmg itself being'well understood is not detailed on the drawing.

Passing through the furnace body along the upper and lower outer margins of the tubular blocks 11 are pipes 20 for water circulation to prevent overheating the terminals.

At one or both ends of the furnace are observing or cleaning openings 21 and 22 which are suitably plugged with a block of refractory during the operation of the furnace, while also atone or both ends in the plane of the tools is inserted a suitable thermo-couple as indicated at 23 wired in the known manner (not shown) for indicating the temperature of the tool-plane, since it projects into the'furnace in that plane. a

In contemplating my invention it will be seen that when the slot is filledwith tools it is substantially closed by the larger ends of the-tools positioned just within the inner and con trolled from suitable switch blocks 18 and edge of the slot, and of course it is evident that when fewer tools are being handled refractory blocks may be passed along with the tools to keep the slot closed, also that while I show but an enlargement at each end of the slot for insertion and withdrawal of the tools. it is within the scope of the invention to form anv number of such enlargements, and to plug up with a block of refractory any such enlargements or portion of the slot not being used.

I claim 1. A furnace provided with means for heating the same and a slot in the side of the furnace adapted for the insertion of tools to be heated for passage along the slo said slothaving enlargements at spaced points for the passage of the heads of the tools and, a restricted portion to prevent their withdrawal connecting the enlargements.

2. A furnace provided with means for heating the same and a slot in the side of the furnace adapted for the insertion of tools to be heated for passage along the slot said slot being inclined to facilitate passage of the tools therealong toward the lower end of the slot.

3. In a furnace of the character described,-

a furnace chamber traversed by a row of spaced electrical heating elements, and means for passing a row of drill bits to be heated successively past said elements while projecting at their shanks from the furnace.

4. In a furnace of the character described, a furnace chamber traversed by a row of spaced electrical heating elements. means for presenting a row of tools into said chamber adjacent said heating elements, and means for energizing said elements selectively in groups.

. 5. In a furnace of the character described a furnace chamber traversed by spaced rows ofelectrical heating elements. and means for presenting a row of drill tools into said chamber between the rows of elements for heating the tools freely exposed at opposite sides to the radiant heat thereof.

6. In a furnace of the character described a furnace chamber traversed by spaced rows of electrical heating elements, and means for presenting a row of drill tools into said chamber between the rows of elements for heating the tools and means for indicating the temperature of the zone between the elements. 1 M

HAROLD K. FOX. 

